Articles requiring a degree of elasticity have been formed by combining elastic core materials with inelastic, or less elastic, facing materials through various lamination processes. Often, such composite laminate articles will be stretchable because of the presence of the elastic core material and the particular manner in which the elastic core and inelastic facing materials have been bonded together during the laminating process.
Typically, such stretchable laminates are formed by joining the inelastic facing material to the elastic core material while the elastic core material or sheet is in a stretched condition. After such joining of the materials, the laminated article is then allowed to relax, which results in the inelastic component gathering in the spaces between bonding sites on the elastic sheet. The resulting laminate article is then stretchable to the extent that the inelastic material gathered between the bond locations allows the elastic material to elongate. Examples of these types of composite stretch bonded laminate articles and materials are set forth in U.S. Pat. Nos. 4,720,415 and 5,385,775, each of which is incorporated herein by reference thereto.
In some stretchable laminate articles, the elastic core material includes elastic strands of continuous filaments that are bonded to the relatively inelastic facing sheet materials while the elastic strands are in a stretched condition. Such elastic continuous filaments may, in certain articles, be sandwiched between two or more relatively inelastic sheets. The relatively inelastic sheets may include nonwoven webs formed by meltblowing or spunbonding various polymers. Examples of such laminates and processes for making are shown in U.S. Pat. No. 5,385,775 to Wright and copending U.S. Patent Application Publication 2002/0104608A1 to Welch et al., each of which is incorporated herein in its entirety by reference thereto.
Such laminated articles may be utilized in various products requiring a certain degree of stretchability and elasticity, such as diapers, garments, drapes, pads, and the like. In producing the various products that utilize stretchable elastic laminated articles, the elastic laminated articles are unwound from large rolls of material upon which the laminated articles are stored. The stretchable nature of the laminated articles can result in problems during the manufacturing process of the ultimate products. For example, the force required to unwind the rolled articles can at least partially extend the elastic laminate while the elastic article is in tension. This partial extension of the stretchable laminate can make it difficult to properly measure and position the desired quantity of the elastic article in the final product. Therefore, there remains a need in the art for low cost elastic laminate materials that have less than the final desired stretch during the process of cutting and placing the material in a final product, but which achieve the desired level of stretch after having been placed in the final product.